500 - Server Error will be sent to the Exception Handler

[kdavisk6]

See #22

Scenario: Simple HTTP request that results in a 5xx response code, is sent to the Exception Handler.

Given: a request is made to a known endpoint,
When: the request is sent to the target,
And: a response is returned with a 5xx response code
Then: the exception handler is invoked.

Additional Context
This test case should not attempt to decode the response into the desired response type because an error occurred. That should be up to the Exception Handler to manage.